code: def forward(
      self,
      input: torch.Tensor,
      ilens: torch.Tensor,
      additional: Optional[Dict] = None,
  ) -> Tuple[Tuple[torch.Tensor], torch.Tensor, OrderedDict]:
      raise NotImplementedError
  
file_path: espnet/espnet2/enh/separator/abs_separator.py
imports: from abc import ABC, abstractmethod
  from collections import OrderedDict
  from typing import Dict, Optional, Tuple
  import torch
label_desc: Use image node_id 1 for calling the AbsSeparator obj's underlying member method code with example usage: obj.forward(input, ilens, additional) without return types